- 28 70. The delegation was also struck by the variety of persons detained in the basement area. As might have been expected, the delegation met criminal suspects awaiting a judicial decision on their release or remand in custody as well as persons held under the Aliens legislation. However, it also encountered persons who had actually been remanded in custody and were awaiting trial and - most astonishingly of all - sentenced prisoners; apparently, this was a result of severe overcrowding at Thessaloniki Prison. Some of the persons in question had been held at the Headquarters for well over a month. As at Athens Police Headquarters, the physical surroundings and regime in the detention facilities at Thessaloniki Police Headquarters render these premises unsuitable for lengthy stays. Further, to hold a person on remand or - a fortiori - a sentenced prisoner in these facilities is inadmissible (and apparently contrary to Greek law); such persons are entitled to expect a quite different custodial environment. 71. As regards the detention facilities at Thessaloniki Police Headquarters, the CPT wishes to make the following recommendations: - that remand and sentenced prisoners should not be held in these facilities (but instead in an appropriate prison establishment); - that no-one be held in these facilities for longer than is absolutely necessary; - that the two segregation cells remain out of service until such time as they are brought into conformity with the criteria set out in paragraph 52; - that there be a maximum occupancy level of four or five persons per cell (depending on the cell size) in the multi-occupancy cells in the basement area (with a possible exception as regards persons only staying a few hours in custody); - that persons detained overnight be provided with both blankets and their own mattress; - that the toilet/shower facilities be kept in a hygienic condition, and detained persons provided with the wherewithal to keep themselves clean: - that means be sought of enabling persons detained for more than 24 hours to be offered outdoor exercise on a daily basis; - that persons detained under the Aliens legislation be strictly separated from criminal suspects; - that an information leaflet be given to persons detained under the Aliens legislation explaining the procedure applicable to them and their related rights; this leaflet to be available in the languages most commonly spoken by such persons, and, if necessary, the services of an interpreter provided. 72. The delegation also visited Police Station No. 3, in Alexander Svolou St. This station possessed one cell, measuring 3 m². The cell enjoyed adequate light (both natural and artificial) and ventilation, was clean, and was equipped with a means of rest (i.e. a concrete block with a mattress and blanket). Nevertheless, in view of the cell's very small size, it should only be used for temporary holding purposes (i.e. detention for a maximum of a few hours); the cell is not suitable for the detention of someone obliged to stay in police custody overnight.